Laravel: Get column value from first() result of relationship query - php

Question

I'm trying to get a single column value from the first result of a Model's belongsToMany relationship query, as i'm returning the ->first() result of the relationship I was hoping $code->reward->title would work but it doesn't.
I get an Relationship method must return an object of type Illuminate\Database\Eloquent\Relations\Relation error
What I'm trying to do is the get the title of the current reward that is linked to a specific code - the code_reward pivot table has a valid_from and expires_at date as the reward linked to a code will change as time goes by, hence the need to get the currently active reward for that code.
Here's my code:
Model: Code
public function rewards()
{
return $this->belongsToMany('App\Reward')->withPivot('valid_from', 'expires_at')->withTimestamps();
}
public function reward()
{
$now = Carbon::now();
return $this->rewards()
->wherePivot('valid_from', '<', $now)
->wherePivot('expires_at', '>', $now)
->first();
}
Controller: CodeController
public function index()
{
$codes = Code::all();
return view('codes/index')->with('codes', $codes);
}
View: Codes/index
#foreach ($codes as $code)
{{$code->id}}
{{$code->reward->title}}
#endforeach
Any help is really appreciated!
Update
Unfortunately both suggestions below ($code->reward()->title and getRewardAttribute() return an Trying to get property of non-object error.
If I remove ->first() from the Code->reward() method and replace $code->reward->title with $code->reward->first() in the view it echoes out the whole reward model as json, however $code->reward->first()->title still returns the Trying to get property of non-object error
Update 2
If I do {{dd($code->reward->title)}} in the view I get the reward title but if I just do {{$code->reward->title}}, I don't!
AND the $code->reward->title works as expected in a #Show view, so could it be that the collection of codes supplied by the controller's #index method isn't passing the necessary data or not passing it in a necessary format??
SOLVED
The issue was caused by one of the $code->rewards in the foreach loop in the index view returning null! The first one didn't, hence the dd() working but as soon as the loop hit a null it crashed.
Once I wiped and refreshed the db (and made sure my seeds where adding only valid data!) it worked. Doing {{$code->reward ? $code->reward->title : ''}} fixed the issue. Grrr.

Answer 1

Your statement is failing because $code->reward->title tells Laravel that you have defined a relationship on your Code model in a method called reward(). However, your relationship is actually defined in the method rewards(). Instead, reward() is a custom method on the model that you have made up. Calling it as a method and not a relation is the quickest way to get what you want.
{{$code->reward()->title}}
As #andrewtweber points out below, you could also make your custom reward() method into an attribute accessor. To do that, just rename the function to getRewardAttribute() and then you can call it in your view like you originally did.
Alternatively, you could get rid of that reward() method entirely and move all of that logic to the controller, where it probably makes more sense. You'd have to use constrained eager loading to pull that off. So in your controller you'd have something like this:
$codes = App\Code::with(['rewards' => function ($query) {
$query->wherePivot('valid_from', '<', $now)
->wherePivot('expires_at', '>', $now);
])->get();
Of course, this would return all of your filtered codes. This is because you cannot apply a sql limit inside a nested eager relationship as outlined here. So in your view, you would then have to do something like this:
{{$code->rewards->first()->title}}
However, it will be simpler to go with my first solution, so that's entirely up to you.

Answer 2

Try to set this method in Code Model, because query builder treats valid_from and expired_at as string, not date?
public function getDates()
{
return ['valid_from','expired_at'];
}